Symphyotrichum subulatum |
Symphyotrichum chapmanii |
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annual saltmarsh American-aster, annual saltmarsh aster, annual saltmarsh or eastern annual saltmarsh aster, aster subulé, eastern annual saltmarsh aster, Southwestern annual saltmarsh aster |
savanna aster |
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Habit | Annuals, (10–)30–150 cm; tap-rooted. | Perennials, 30–80 cm, cespitose; rhizomes stout. | ||||||||||||||||
Stems | 1, erect (often with purple or purplish brown areas), glabrous or glabrate, sometimes strigillose in leaf axils. |
1–3+, erect (sometimes brown proximally, strict to straight), glabrous. |
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Leaves | thin (green to dark green), margins often strigilloso-ciliolate, faces glabrous; basal withering by flowering, long-petiolate (petiole bases sheathing), sparsely ciliate, blades ovate to oblanceolate, 10–90 × 6–14 mm, bases attenuate to cuneate, rounded, margins entire or serrulate or crenulate, apices rounded, obtuse, or acute; proximal cauline withering by flowering, petiolate, subpetiolate, or sessile, blades narrowly lanceolate or subulate, 20–100(–200) × 1.5–10(–20) mm, bases attenuate, margins subentire, entire, or serrulate, apices acute to acuminate; distal sessile, blades narrowly lanceolate to subulate, 5–113 × 0.5–5.5 mm, apices acuminate. |
green to dark green, firm, ± fleshy, margins entire, ciliate, apices acute, callous, faces sparsely strigillose; basal persistent or petiole bases marcescent, long-petiolate (to 15 cm; petioles sheathing, margins glabrous), blades linear to linear-lanceolate, 10–30 × 2–7 mm, bases cuneate to subattenuate, margins sparsely denticulate or entire, indurate-translucent; proximal cauline persistent, sessile or subpetiolate, blades linear, 42–105 × 1–3 mm, bases clasping, margins often revolute; distal sessile, blades usually linear, sometimes awl-shaped, 50–180 × 5–10 mm, strongly reduced distally, more abruptly so on array branches, bases subclasping to adnate for 1/2+ length, margins often revolute. |
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Peduncles | (0.2–)0.5–4 cm, bracts 4–8(–17). |
1–20+ cm, slender, glabrous, bracts 4–22, linear (awl-shaped), grading into phyllaries. |
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Involucres | cylindric to turbinate, 5–7(–8.2) mm. |
cylindro-campanulate, 5.5–9 mm. |
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Ray florets | 16–30(–54) in 1–3 series; corollas white, pink, or lavender, laminae 1.3–7 × 0.2–1.3 mm. |
8–23; corollas purple to blue-lavender, laminae (10–)14–15(–20) × 0.8–2.2 mm. |
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Disc florets | 4–10(–13); corollas yello, sometimes tinged with purple, 3.4–5.2 mm, throats narrowly funnelform, lobes ± spreading to erect, narrowly triangular, 0.3–0.7 mm, glabrous. |
47–57; corollas pale yellow, 4.7–6.3 mm, throats funnelform to narrowly campanulate, lobes triangular, 0.5–0.7 mm (proximally sparsely pilose). |
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Phyllaries | in 3–5 series, broadly or narrowly lanceolate to subulate, unequal, bases indurate, margins hyaline, often purple-tinged, entire, green zones lanceolate (usually narrow, sometimes broad and covering most of distal portion), apices acute, faces glabrous. |
in 4–5(–6) series, oblong-lanceolate (outer) to linear-lanceolate (innermost), bases indurate (at least inner), margins scarious, hyaline, purplish distally, ciliolate, green zones narrowly lanceolate, not evident, apices purplish, acute (outer) to acuminate (inner), sometimes mucronate (inner), faces sparsely villous. |
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Heads | (10–) 30–100(–150), in open, diffuse, paniculiform arrays. |
in open, usually corymbiform, sometimes ± paniculiform arrays, branches ascending, simple, slender, elongate. |
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Cypselae | light brown to purple, narrowly obovoid to fusiform, sometimes ± compressed, (1.2–)1.5–2.7(–3) mm, 5-nerved, faces sparsely strigillose; pappi white, (3–)3.5–5.5 mm. |
tan to gray-brown (nerves stramineous), obovoid, compressed, 3.1–4.5 mm, 8–10(–14)-nerved, faces glabrous; pappi yellowish, 4.4–4.7 mm. |
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2n | = 14. |
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Symphyotrichum subulatum |
Symphyotrichum chapmanii |
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Phenology | Flowering Sep–Nov(–Dec). | |||||||||||||||||
Habitat | Wet savannas, pine flatwoods, bogs, and acid swamps | |||||||||||||||||
Elevation | 0–30 m (0–100 ft) | |||||||||||||||||
Distribution |
AL; AR; AZ; CA; CT; DE; FL; GA; IL; IN; KS; LA; MA; MD; ME; MI; MS; NC; NE; NH; NJ; NM; NV; NY; OH; OK; PA; RI; SC; TN; TX; UT; VA; NB; ON; Mexico; Central America; South America; West Indies; Bermuda [Widely introduced worldwide]
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AL; FL |
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Discussion | Varieties 5 (5 in the flora). Five varieties of Symphyotrichum subulatum are recognized for North America based on differences in chromosome number, ray lamina color and size, array shapes, number of series of ray florets, number of disc and ray florets, and other, more cryptic characters (S. D. Sundberg 2004). These varieties were treated as species by G. L. Nesom (1994b, 2005d). Variety ligulatum is apparently an obligate outcrosser and is the least variable variety (Sundberg). Other varieties are self-compatible, which could facilitate the fixation of mutations in populations. The five varieties are nearly entirely allopatric, and intermediates between pairs of varieties are not uncommon where they approach one another. Populations that are intermediate in ray lamina size between vars. ligulatum and parviflorum are widespread in southern Texas, New Mexico, Arizona, and northern Mexico. Intermediates between vars. elongatum and parviflorum and between vars. elongatum and subulatum occur in Florida. Despite these observations, hybridization experiments and chromosome number differences suggest that the varieties are mostly reproductively isolated (S. D. Sundberg 1986, 2004). In older floras the name Aster exilis Elliott has been applied to Symphyotrichum subulatum vars. ligulatum and parviflorum. The status of this name is uncertain; the type specimen has been lost and the description of the plant is inadequate for determining the taxon to which the name should be applied (G. L. Nesom 1994b; S. D. Sundberg 2004). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Symphyotrichum chapmanii is known from the Appalachicola Valley, northern Florida and adjacent southeast Alabama (where it is possibly extirpated), and is disjunct to St. Lucie County (Florida). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 480. | FNA vol. 20, p. 478. | ||||||||||||||||
Parent taxa | Asteraceae > tribe Astereae > Symphyotrichum > subg. Astropolium | Asteraceae > tribe Astereae > Symphyotrichum > subg. Chapmaniani | ||||||||||||||||
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Synonyms | Aster subulatus | Aster chapmanii, Eurybia chapmanii, Heleastrum chapmanii | ||||||||||||||||
Name authority | (Michaux) G. L. Nesom: Phytologia 77: 293. (1995) | (Torrey & A. Gray) Semple & Brouillet: in J. C. Semple et al., Cult. Native Asters Ontario, 133. (2002) | ||||||||||||||||
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